MacEwan Open Journals (MacEwan University)
Not a member yet
2252 research outputs found
Sort by
The extraction of undecaprenol from sumac leaves
No full textBacterial cells are fortified by an outer layer of peptidoglycan and lipid II is the key precursor molecule in the biosynthesis of peptidoglycan. Lipid II is comprised of several units: a disaccharide moiety, a pentapeptide, and a C55 undecaprenyl chain, which attaches to the disaccharide via a pyrophosphate linker. Since lipid II plays a key role in providing structure and integrity to bacterial cells, it is an attractive target for the development of novel antimicrobial agents. Such studies require the ability to synthesize lipid II and its analogues. However, one of the limitations to synthesizing lipid II is the preparation of the C55 lipid chain. While this molecule is difficult to synthesize, its immediate precursor, undecaprenol (C55-OH) can be extracted from sumac leaves. In this project, we describe the isolation of undecaprenol from the leaves of the sumac tree (Rhus typhina) and its purification by HPLC. At the conclusion of the procedure, roughly 20 mg of undecaprenol was collected. Two major results of the project are presented: first, the development of a simple method to extract this important compound from an abundant and renewable source; and second, the observation of the instability of undecaprenol.
*Indicates presente
Development of culture medium for high density micropropagation of potato plants in vitro
No full textAll commercial seed potatoes start off as small plantlets grown in tissue culture, and in vitro clonal micropropagation is the only way to ensure a constant supply of certified virus-free plants. Selecting the correct culture medium is one of the most important steps in developing a useful protocol for successful growth and propagation of plant species in vitro. In Alberta, all commercial tissue culture labs rely on the classic Murashige and Skoog (MS) medium to clonally propagate potato plants in vitro. Although MS composition is widely used as a standard growth medium, the nutrients it supplies may not be optimal for plant growth on an industrial scale. To meet the growers’ demand for seed potatoes, commercial producers have to grow plants at 4–10 times higher densities than those in research laboratories. The resulting plants are often of poor quality and exhibit reduced survival rate after being transferred to the greenhouse, thereby causing serious economic losses for the industry. Hence, the composition of MS medium likely requires major modifications to improve its efficiency for commercial use, particularly when potato plants are grown in culture vessels at high density and suboptimal culture conditions. The aim of this study was to evaluate the effects of additional MS nutrients on shoot quality and to determine the most critical culture medium components for improved plant growth response in potato. A factorial approach was used to test combinations of five nutrient factors: 1) NH4NO3, 2) KNO3, 3) mesos (CaCl2, KH2PO4 and MgSO4), 4) micronutrients (B, Cu, Co, I, Mn, Mo, Zn, Fe), and 5) source of carbohydrates. Each factor varied over a range of concentrations, added to MS medium. In total, 25 medium compositions were tested. The effects of these treatments on plant quality, such as shoot length, leaf size and color, were determined. An increase of mesos and micronutrients to concentrations four times higher than in the original MS medium was found to be the most significant factor associated with plant quality, multiplication and shoot length in all plants. This optimized growth medium can be used to produce higher quality potato plants in vitro.
*Indicates presente
Metabolomic Profiling of Gestational Diabetes Mellitus: A 1H-NMR Based Approach
No full textIntroduction: Gestational diabetes mellitus (GDM) has been shown to increase the occurrence of pregnancy complications, including preeclampsia, preterm births, caesarean sections, intrauterine growth retardation, and neonatal intensive care unit admissions. Current tests for diagnosing GDM and pre-diabetic states in pregnancy are time-consuming and often unreliable. Our main objective was to characterize any metabolomic differences in the urine of women with GDM and healthy pregnant controls to identify diagnostic and predictive biomarkers.
Methods: Urine samples from the second trimester of pregnancy from 33 women with GDM and 34 age-, income-, and education-matched healthy controls were obtained from the Alberta Pregnancy Outcomes and Nutrition (APrON) cohort. Proton nuclear magnetic resonance (1H-NMR) data was acquired using a 700 MHz spectrometer and subsequently binned for data analysis. Group separation was evaluated using principle component analysis (PCA) and partial least square discriminant analysis (PLS-DA). Variable importance analysis based on random variable combination (VIAVC) and Mann-Whitney testing were used to determine which metabolites were significantly altered across the comparison groups. Lastly, pathway analysis was carried out to determine which biological pathways were potentially altered by these metabolites.
Results: The analyses revealed group separation between the metabolomic profiles of pregnant women diagnosed with GDM and health pregnant controls. Several significantly altered metabolites, along with some potentially altered biological pathways, were identified across the comparison groups.
Conclusions: These results demonstrate the potential for 1H-NMR and metabolomics to diagnose pregnant woman with, or assess their risk for developing, GDM. Furthermore, the subset of metabolites identified as significantly altered provides potential biomarkers that can be correlated with pregnancy outcomes in order to identify women at high risk of negative pregnancy outcomes.
*Indicates presente
Detecting chemical modifications of Ribonucleic Acid
No full textTransfer Ribonucleic acid (tRNA) is one of the highly chemically modified RNA in the cell, and the isomerization of uridine to pseudouridine (ᴪ) is the most abundant RNA modification found in all domains of life. Although the function of RNA modification is not yet fully understood, the chemical changes in RNA have been implicated in cellular fitness and development of genetic diseases. For example, the bacterial proteins TruA and RluA are both pseudouridine synthases which catalyze the isomerization of uridine to pseudouridine. TruA is capable of modifying several nearby sites in tRNAs while RluA modifies different RNAs at positions with a shared sequence and structure. These modifications are conserved in all forms of life, but little is known about their function.
The objective of this research project was to modify tRNA using modification enzymes and to establish a method to detect multiple RNA modifications at once using High Performance Liquid Chromatography (HPLC). Using a reverse phase chromatography column will allow to separate samples based on hydrophobicity. On one side, tRNA was successfully in vitro transcribed, purified and digested into nucleosides, which were then separated using the HPLC column. On the other side, TruA and RluA wild-type proteins were successfully overexpressed and purified, in order to prepare modified tRNA. In the future, this system will enable us to detect and quantify the presence of pseudouridine as well as other chemical modifications in any type of RNA. This tool will thereby greatly advance research in the Kothe lab to understand the mechanisms and functions of RNA modifications.
*Indicates presente
Eukaryotic Initiation factor 5B (eIF5B) provides glioblastoma multiforme with resistance towards apoptotic agents
No full textEukaryotic initiation factors (eIFs) are proteins involved in the general process of mRNA translation. However, under conditions of physiological stress, alternative methods of translation initiation are often activated and relied upon to continue translation of a subset of mRNAs. Specific eIFs such as eIF5B have been shown to use cap-independent mechanisms to promote the production of anti-apoptotic proteins, such as X-linked inhibitor of apoptosis protein (XIAP). In the present study, we have explored if eIF5B provides resistance to glioblastoma multiforme (GBM) cells towards apoptotic agents.
Using siRNA, we depleted eIF5B from various GBM cells and treated them with agents that promote apoptosis. In order to activate intrinsic apoptosis pathway we treated these cells with genotoxic agents such as doxorubicin (DXR), and temozolomide (TMZ). Moreover, we treated GBM cells with tumor necrosis factor alpha (TNFα), and/or TNF-related apoptosis-inducing ligand (TRAIL) to activate extrinsic apoptosis pathway. The depletion of eIF5B did not sensitize GBM cells to DXR or TMZ. However, further viability assays showed that knockdown of eIF5B sensitized U343 cells to TRAIL or TRAIL + TNFα. Further, the combination of TRAIL + SMAC- mimetic compounds (SMC) showed statistically significant decreases in cell viability when eIF5B was depleted. So far, six different glioblastoma cell lines have been assessed for this effect, and further studies are underway to observe the effects of eIF5B depletion on cell viability of various cancer and non-cancer cells. Our preliminary data suggest that eIF5B enhances cell survival of GBM cells and could represent a potentially important therapeutic target.
*Indicates presente
Consumerization of HR: The Employee Consumer Style Experience
No full textEmployee consumer style relationships means exactly as it sounds, a customer type experience for the employee. Human Resource experts have found this topic as a trending factor to benefit businesses today. Looking internally as opposed to externally, businesses can gain a competitive advantage while retaining staff. This presentation informs the audience on what specifically is being done by businesses who have implemented ways to provide the “employee experience”. In contrast, a particular industry that lacks these practices. To conclude, some recommendations to help shift the industry in an internal direction.
Discipline: Accounting
Faculty Mentor: Dr. Leo Won
Reducing False Polarization Through Perceptions of Friendship and Intelligence
No full textPeople tend to believe they see the world objectively. Accordingly, people perceive disagreeing others as biased, and think they’re more extreme than they really are. We hypothesized whether individuals will see adversaries as less biased and extreme when they perceive them as competent, and when they’ve formed a friendship. Participants came to the lab in pairs. Pairs were randomly assigned to engage in a procedure known to induce friendship, or control procedure. Participants were also randomly assigned to receive information indicating each other to be of either average or high intelligence. Participants then saw a marijuana legalization opinion disagreeing with their own, supposedly from the other participant. Finally, participants indicated how they perceived the other participant’s competence, extremity of political ideology, and estimated extremity of stance on marijuana legalization. They also indicated these same perceptions on the average person holding this disagreeing opinion to see if any effects would generalize from the individual to the group level. Perceptions of the interaction partner person weren’t changed across conditions. Surprisingly, the friendship manipulation (but not the competence manipulation) reduced perceptions of bias and ideological extremity in the average person holding a disagreeing opinion. No effects were observed of either manipulation on perceived attitude extremity. Implications and future directions are discussed.
Discipline: Psychology (Honours)
Faculty Mentor: Dr. Craig Blat
Interstellar: A Visual Structure of the Film
No full textMy creative interpretation of the film Interstellar displays the non-linear timeline of the movie in the shape of Einstein’s diagram of the Theory of Relativity. The main character in Interstellar, Coop, travels through space to attempt to find a new world to save the human population. Because of the gravity of Gargantua, a black hole, time is warped. My infographic poster displays how Coop’s space timeline and the Earth’s time coordinate and happen simultaneously. Beginning at the bottom of the diagram, the timeline runs counter clockwise, matching the significant events on Earth with the corresponding events happening in Space. In the infographic, each line on the cone represents 5 minutes in the movie. The Earth timeline loops because the actions happening in the past overlap with Murph’s (Coop’s daughter) life in the latter half of the movie. Reoccurring actions are marked by icons on the timeline, and significant actions and simultaneous actions are colour coded. A model of the Relativity of Space and Time is provided so the reader can see that the shape of the infographic is displayed based on a scientific diagram. This poster displays the timeline of Interstellar in a visual and comprehensive way, using a scientific model to communicate the information. It simplifies the seemingly-confusing time jumping from Earth to Space time.
Discipline: Design Studies
Faculty Mentor: Constanza Pache
Effect of Acute and Chronic Nicotine Exposure on Anxiety-like Behaviour in Zebrafish
No full textNicotine is an addictive compound that acts through the activation of nicotinic acetylcholine receptors (nAChRs ). Zebrafish (Danio rerio) are becoming an increasingly important animal model for pharmacological research and demonstrate varied effects of acute nicotine exposure on behaviour. For example, nicotine enhanced spatial position discrimination learning and increased object recognition memory. However, there have been opposing results on nicotine\u27s action on anxiety-like behaviour and no studies examining the impact of withdrawal following chronic nicotine administration. In order to examine the effects of chronic and acute nicotine exposure on anxiety-like behaviour in wild-type adult zebrafish, we administered single doses of 25, 50, 100, or 400mg/L for acute experiments, or 2.5 , 5, or 20mg/L one-hour doses per day for 21 days for chronic experiments. Anxiety-like behaviours were observed using the novel object approach test which involves placing a fish in a circular arena containing a novel object placed in the center. Time spent in the outer (thigmotaxis), middle (transition), and inner zones, distance moved, and immobility were measured with a motion tracking software. Acute doses of nicotine significantly increased time spent in the transition zone, and significantly decreased time spent in the thigmotaxis zone indicating decreased anxiety. On the contrary, chronic nicotine exposure at 20 mg/L significantly increased anxiety as indicated by an increased time spent in the thigmotaxis zone. This study demonstrates that acute nicotine exposure decreases anxiety-like behaviour whereas chronic exposure causes increased anxiety-like behaviour during withdrawal.
Discipline: Psychology (Honours)
Faculty Mentor: Dr. Trevor Hamilton
 
A Meta-Analysis of Faith Based Correctional Programming
No full textThis presentation is a meta-analysis and summary of themes correlated with faith-based programming in correctional institutions such as jails, remand facilities, and prisons. The research presented is a component of a larger honours project examining the use of faith-based rehabilitation programming within a targeted jurisdiction in the Midwest United States.
Discipline: Sociology (Honours)
Faculty Mentor: Dr. Michael Seredyc